Swing analyzing device, swing analyzing method, storage medium, and swing analyzing system

ABSTRACT

A calculator matches a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing and calculates a divergence degree between the first time series information and the second time series information. A determiner determines, on the basis of the divergence degree between the first time series information and the second time series information, whether the first swing and the second swing are approximate to each other.

BACKGROUND

1. Technical Field

The present invention relates to a swing analyzing device, a swing analyzing method, a storage medium, and a swing analyzing system.

2. Related Art

JP-A-2008-73210 (Patent Literature 1) discloses a technique for attaching a sensor to a golf club, analyzing swing behavior, and supporting evaluation of a swing.

However, even if a swing result such as speed and a track of a swing is indicated by a golf-swing analyzing device including an inertial sensor, it is difficult for a user to objectively grasp whether the swing of the user is good.

For example, some golf-swing analyzing device displays a swing track of a user and a swing track ideal for a professional golfer or the like one on top of the other. However, only with the comparative display of the tracks, it is difficult for the user to objectively grasp whether the swing of the user is good.

SUMMARY

An advantage of some aspects of the invention is to provide a technique for enabling a user to objectively grasp whether a swing of the user is good.

A first aspect of the invention is directed to a swing analyzing device including: a calculator configured to match a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and a determiner configured to determine, on the basis of the divergence degree between the first time series information and the second time series information, whether the first swing and the second swing are approximate to each other.

According to the first aspect, a user can objectively grasp whether a swing of the user is good.

The determiner may determine, on the basis of whether the divergence degree is equal to or larger than a threshold set in advance, whether the first swing and the second swing are approximate to each other.

The predetermined point in time may be an impact.

With this configuration, the user can objectively grasp whether a swing near the impact, which is an important indicator of the swing, is good.

The calculator may calculate the divergence degree in a predetermined section between the first time series information and the second time series information. Consequently, the user can objectively grasp whether a swing in the predetermined section is good.

The predetermined section may be at least a part of a downswing.

With this configuration, the user can grasp whether a swing is good in at least a part of the downswing, which is an important indicator of the swing.

The predetermined section may be selectable.

With this configuration, the user can select a section where the user would like to grasp whether a swing is good.

The determiner may select a plurality of the predetermined sections and change, in one of the predetermined section and the other, the threshold for determining whether the first swing and the second swing are approximate to each other.

With this configuration, it is possible to vary a reference for determining whether the first swing and the second swing are approximate to each other in a section where a swing is important and a section where the swing is not important.

The first time series information may be a coordinate of a track of the first swing, the second time series information may be a coordinate of a track of the second swing, and the divergence degree may be a distance between the coordinate of the track of the first swing and the coordinate of the track of the second swing.

With this configuration, the user can grasp whether a swing is good at swing speed and in a swing route.

The first time series information may be an angle of a ball hitting surface of an exercise instrument in the first swing, the second time series information may be an angle of a ball hitting surface of the exercise instrument in the second swing, and the divergence degree may be a difference between the angle of the ball hitting surface of the exercise instrument in the first swing and the angle of the ball hitting surface of the exercise instrument in the first swing.

With this configuration, the user can grasp whether a swing is good at an angle of a ball hitting surface of the exercise instrument.

The swing analyzing device may further include an image generator configured to generate image data such that display forms are different in a portion where the first swing and the second swing are approximate to each other and a portion where the first swing and the second swing are not approximate to each other.

With this configuration, the user can easily grasp whether a swing of the user is good.

A second aspect of the invention is directed to a swing analyzing method including: matching a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and determining, on the basis of the divergence degree between the first time series information and the second time series information, whether the first swing and the second swing are approximate to each other.

According to the second aspect, a user can objectively grasp whether a swing of the user is good.

A third aspect of the invention is directed to a computer program for causing a computer to execute: matching a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and determining, on the basis of the divergence degree between the first time series information and the second time series information, whether the first swing and the second swing are approximate to each other.

According to the third aspect, a user can objectively grasp whether a swing of the user is good.

A fourth aspect of the invention is directed to a swing analyzing system including: an inertial sensor; and a swing analyzing device including: a calculator configured to match a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and a determiner configured to determine, on the basis of the divergence degree between the first time series information and the second time series information, whether the first swing and the second swing are approximate to each other.

According to the fourth aspect, a user can objectively grasp whether a swing of the user is good.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.

FIG. 1 is a diagram showing a configuration example of a swing analyzing system according to a first embodiment.

FIG. 2 is a diagram showing an example of functional blocks of a sensor unit and a swing analyzing device.

FIGS. 3A and 3B are a diagram for explaining an example of a relation between tracks and events of a reference swing and a comparative swing.

FIG. 4 is a diagram for explaining an example of matching of predetermined points in time of coordinates of two tracks.

FIGS. 5A and 5B are a diagram for explaining an example of a divergence degree between two swings.

FIG. 6 is a flowchart for explaining an operation example of the swing analyzing device.

FIG. 7 is a diagram showing an example of functional blocks of a sensor unit and a swing analyzing device according to a second embodiment.

FIG. 8 is a diagram showing a screen example of a reference swing and a comparative swing.

FIG. 9 is a flowchart for explaining an operation example of the swing analyzing device.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Embodiments of the invention are explained below with reference to the drawings.

First Embodiment

FIG. 1 is a diagram showing a configuration example of a swing analyzing system according to a first embodiment. As shown in FIG. 1, the swing analyzing system includes a sensor unit 1 and a swing analyzing device 2. The sensor unit 1 and the swing analyzing device 2 can perform communication with each other by wireless communication or wired communication. In FIG. 1, a golf club (equivalent to the exercise instrument according to the invention) C1 and a user U1 who swings the golf club C1 are shown.

The sensor unit 1 includes an inertial sensor and measures accelerations in axial directions of three axes, which are in a substantially orthogonal relation, and angular velocities generated around the three axes. For example, the sensor unit 1 is attached to a part of a shaft of the golf club C1 with a y axis among three detection axes of x, y, and z axes set in the longitudinal direction of the shaft of the golf club C1. The sensor unit 1 measures accelerations in the three axial directions of the golf club C1 and angular velocities around the three axes generated by a swing of the user U1. The sensor unit 1 transmits the generated accelerations and angular velocities (hereinafter sometimes referred to as measurement data) to the swing analyzing device 2.

The swing analyzing device 2 is a terminal device such as a smartphone or a personal computer. In the example shown in FIG. 1, the swing analyzing device 2 is the smartphone and is attached to the waist of the user U1.

The swing analyzing device 2 receives the measurement data transmitted from the sensor unit 1 and analyzes a swing motion of the golf club C1 on the basis of the received measurement data. For example, the swing analyzing device 2 analyzes a swing motion such as a track (e.g., a track of a head) of the golf club C1.

The swing analyzing device 2 receives a swing ideal for the user U1 in advance from the user U1. For example, the swing received in advance may be a swing in the past when a condition of the user U1 was good or may be a swing of a professional golfer ideal for the user U1.

As explained in detail below, when the user U1 swings the golf club C1, the swing analyzing device 2 determines whether a track of the swing and a track of the swing ideal for the user U1 received in advance are approximate to each other. For example, the swing analyzing device 2 displays, on a display, or outputs, as sound, a result of the determination concerning whether the swing of the user U1 and the ideal swing are approximate to each other. In this way, the swing analyzing device 2 determines whether the swing of the user U1 and the swing ideal for the user U1 are approximate to each other. Therefore, the user U1 can objectively grasp whether the swing of the user U1 is good.

Note that, in FIG. 1, the sensor unit 1 is attached to the golf club C1. However, the sensor unit 1 may be attached to a part of the body of the user U1. For example, the sensor unit 1 may be attached to an arm of the user U1 and measure a swing motion of the arm of the user U1.

FIG. 2 is a diagram showing an example of functional blocks of the sensor unit 1 and the swing analyzing device 2. As shown in FIG. 2, the sensor unit 1 includes a controller 11, an acceleration sensor 12, an angular velocity sensor 13, and a communicator 14.

The controller 11 comprehensively controls the sensor unit 1. The controller 11 receives measurement data (acceleration data and angular velocity data) respectively from the acceleration sensor 12 and the angular velocity sensor 13, adds measurement time to the received measurement data, and outputs the measurement data to the communicator 14.

The acceleration sensor 12 measures accelerations respectively generated in three axial directions, which are in a substantially orthogonal relation. The acceleration sensor 12 outputs the measured accelerations to the controller 11 as, for example, a digital signal.

The angular velocity sensor 13 measures angular velocities generated around respective three axes, which are in a substantially orthogonal relation. The angular velocity sensor 13 outputs the measured angular velocities to the controller 11 as, for example, a digital signal.

The communicator 14 transmits the measurement data (including the measurement time) output from the controller 11 to the swing analyzing device 2. The communicator 14 receives a control command from the swing analyzing device 2 and outputs the received control command to the controller 11. The controller 11 performs various kinds of processing corresponding to the control command.

The swing analyzing device 2 includes a controller 21, a storage 22, a communicator 23, an operation section 24, a display section 25, a sound output section 26, and a communicator 27.

The controller 21 comprehensively controls the swing analyzing device 2. The controller 21 is realized by, for example, a computer including a CPU (Central Processing Unit), which is an arithmetic unit, a RAM (Random Access Memory), which is a volatile storage device, a ROM (Read Only Memory), which is a nonvolatile storage device, an interface circuit that connects the controller 21 and other units, and a bus that connects these devices. The controller 21 may be realized by an ASIC (Application Specific Integrated Circuit) or the like. The functional sections of the controller 21 are explained below.

In the storage 22, for example, data used for processing by the controller 21 is stored. In the storage 22, measurement data of swings in the past is stored. The storage 22 can be realized by a nonvolatile storage device such as a flash ROM.

The communicator 23 receives measurement data transmitted from the sensor unit 1. The communicator 23 outputs the received measurement data to the controller 21. The communicator 23 receives a control command output from the controller 11. The communicator 23 transmits the received control command to the sensor unit 1.

The operation section 24 acquires operation data from a user. The operation section 24 outputs the acquired operation data to the controller 21. The operation section 24 is, for example, a touch panel provided on a display, buttons, keys, or a microphone.

The display section 25 displays a processing result of the controller 21 as characters, a graph, a table, an animation, or other images. The display section 25 is, for example, an LCD (Liquid Crystal Display), an EPD (Electrophoretic Display), a display including an organic light emitting diode (OLED), a touch panel display, or a HMD (head mounted display).

The sound output section 26 outputs the processing result of the controller 21 as voice or buzzer sound. The sound output section 26 is, for example, a speaker or a buzzer.

The communicator 27 performs communication with a server or the like via a not-shown network or the like.

The functional sections of the controller 21 are explained. The controller 21 includes a motion analyzer 31, an event detector 32, a divergence-degree calculator (equivalent to the calculator according to the invention) 33, an approximation determiner (equivalent to the determiner according to the invention) 34, and an image generator 35. At least a part of the functional sections of the controller 21 can be realized by, for example, the CPU reading out a predetermined computer program stored in the ROM to the RAM and executing the predetermined computer program. The predetermined computer program is, for example, an application program running on an OS (Operating System). The predetermined computer program can be read out from a portable storage medium and installed in the swing analyzing device 2 or can be downloaded from a server on a network and installed in the swing analyzing device 2. The OS and the application program may be stored in the storage 22.

The motion analyzer 31 analyzes a swing motion on the basis of measurement data. For example, the motion analyzer 31 calculates a track of a swing on the basis of the measurement data transmitted from the sensor unit 1. The track of the swing is indicated by, for example, a space coordinate (a three-dimensional coordinate) having the origin in an address position of a head of a golf club.

The motion analyzer 31 receives a swing ideal for the user in advance from the user. For example, the ideal swing received in advance may be a swing in the past when a condition of the user was good or may be a swing of a professional golfer ideal for the user U1.

When receiving a swing in the past as an ideal swing from the user, the motion analyzer 31 acquires measurement data corresponding to the swing received from the user referring to the storage 22 in which the measurement data in the past is stored. The motion analyzer 31 calculates a track of a swing ideal for the user from the measurement data acquired from the storage 22.

When receiving a swing of a professional golfer as an ideal swing from the user, the motion analyzer 31 receives, for example, from the server connected to the not-shown network, measurement data of the swing of the professional golfer received from the user. The motion analyzer 31 calculates, from the measurement data received from the server, a track of a swing ideal for the user.

The motion analyzer 31 can analyze a swing motion such as a swing track from the measurement data using a general technique. For example, the motion analyzer 31 can analyze the swing motion according to a technique disclosed in JP-A-2015-2911.

In the following example, a swing ideal for the user is sometimes referred to as reference swing (equivalent to the first swing according to the invention). A swing compared with the reference swing is sometimes referred to as comparative swing (equivalent to the second swing according to the invention). The comparative swing is, for example, the present (latest) swing of a golf club swung by the user using the sensor unit 1 and the swing analyzing device 2.

The event detector 32 detects an event (rhythm) of the track of the swing motion calculated by the motion analyzer 31. For example, the event detector 32 detects timings of an address, a top, a halfway down, an impact, a follow-through, a finish, aback swing, and a downswing of the track calculated by the motion analyzer 31.

The event detector 32 can detect an event in a swing motion using a general technique. For example, the event detector 32 can detect an event according to the technique disclosed in JP-A-2015-2911.

FIGS. 3A and 3B are a diagram for explaining an example of a relation between tracks and events of the reference swing and the comparative swing. An arrow A1 in FIG. 3A indicates an example of calculation timings of coordinates of the track of the reference swing. The motion analyzer 31 calculates coordinates of a track of a golf club at sample points “t₀, t₁, . . . , t_(n), . . . ”. An interval of the sample points “t₀, t₁, . . . , t_(n), . . . ” coincides with, for example, a sampling cycle at which the sensor unit 1 measures measurement data and is an equal interval.

For example, the motion analyzer 31 calculates coordinates of the track of the reference swing in time series from an address to a finish of a swing motion. Examples of the coordinates of the track of the reference swing calculated by the motion analyzer 31 are shown below the sample points.

An arrow A1 a shown in FIG. 3A indicates timing of the address. That is, a coordinate at the first sample point “t₀” indicates a coordinate in the address of the reference swing.

An arrow A1 b indicates timing of the impact. That is, a coordinate at the sample point “t_(n)” indicates a coordinate at the impact of the reference swing. Note that timings of the address and the impact are detected by the event detector 32.

An arrow A2 in FIG. 3B indicates an example of calculation timings of coordinates of the track of the comparative swing. The motion analyzer 31 calculates coordinates of a track of a golf club at sample points “t₀, t₁, . . . t_(n), . . . ”. An interval of the sample points “t₀, t₁, . . . , t_(n), . . . ” coincides with, for example, a sampling cycle at which the sensor unit 1 measures measurement data and is an equal interval.

For example, the motion analyzer 31 calculates coordinates of the track of the reference swing in time series from an address to a finish of a swing motion. Examples of the coordinates of the track of the comparative swing calculated by the motion analyzer 31 are shown below the sample points.

An arrow A2 a shown in FIG. 3B indicates timing of the address . That is, a coordinate at the first sample point “t₀” indicates a coordinate in the address of the comparative swing.

An arrow A2 b indicates timing of the impact. That is, a coordinate at the sample point “t_(n+3)” indicates a coordinate at the impact of the comparative swing. Note that timings of the address and the impact are detected by the event detector 32.

Referring back to FIG. 2, the divergence-degree calculator 33 matches a predetermined point in time of the coordinates of the track (equivalent to the first time series information according to the invention) of the reference swing calculated by the motion analyzer 31 and a predetermined point in time of the coordinates of the track (equivalent to the second time series information according to the invention) of the comparative swing calculated by the motion analyzer 31 and calculates a divergence degree between the track of the reference swing and the track of the comparative swings.

The predetermined point in time when the coordinates of the two tracks are matched is, for example, an impact. For example, the divergence-degree calculator 33 matches an impact point in time of the coordinates of the track of the reference swing and an impact point in time of the coordinates of the track of the comparative swing and calculates a divergence degree between the track of the reference swing and the track of the comparative swing.

FIG. 4 is a diagram for explaining an example of matching of predetermined points in time of coordinates of two tracks. An arrow A3 in FIG. 4 indicates a part of the sample points of the track of the reference swing and the coordinates at the sample points shown in FIGS. 3A and 3B. An arrow A4 indicates a part of the sample points of the track of the comparative swing and the coordinates at the sample points shown in FIGS. 3A and 3B.

As explained above, the divergence-degree calculator 33 matches the predetermined point in time of the coordinates of the track of the reference swing and the predetermined point in time of the coordinates of the track of the comparative swing. For example, as shown in FIG. 4, the divergence-degree calculator 33 matches the impact point in time (the sample point “t_(n)”) of the coordinates of the track of the reference swing and the impact point in time (the sample point “t_(n+3)”) of the coordinates of the track of the comparative swing.

After matching the impact points in time of the coordinates of the two tracks, the divergence-degree calculator 33 calculates a divergence degree between the two tracks, the coordinate timings of the impacts of which are matched. The divergence degree is, for example, the distance between the coordinates of the two tracks.

For example, the divergence-degree calculator 33 calculates the distance between the two tracks from a coordinate (x_(n), y_(n), z_(n)) of the track at the sample point “t_(n)” of the reference swing and a coordinate (x_(n+3)′, y_(n+3)′, z_(n+3)′) at the sample point “t_(n+3)” of the comparative swing. The divergence-degree calculator 33 calculates the distance between the two tracks from a coordinate (x_(n−1)y_(n−1), z_(n−1)) at the sample point “t_(n−1)” of the reference swing and a coordinate (x_(n+2)′, y_(n+2)′, z_(n+2)′) at the sample point “t_(n+2)” of the comparative swing. Similarly, the divergence-degree calculator 33 calculates the distance between the two tracks at one sample point at a time back to the past (in an address direction) in the two tracks, the sample points of the impacts of which are matched.

The divergence-degree calculator 33 calculates a divergence degree between the tracks of the reference swing and the comparative swing in a predetermined section. The predetermined section is, for example, a downswing of the comparative swing. For example, as explained above, the divergence-degree calculator 33 calculates the distance between the two tracks at one sample point at a time back to the past. However, when a coordinate of the track of the comparative swing is a coordinate at a top, the divergence-degree calculator 33 ends the calculation of the divergence degree and calculates a divergence degree between the tracks of the reference swing and the comparative swing in the downswing section (that is, from the top to the impact).

The distance between the coordinates of the two tracks, the predetermined points in time (the impacts) of which are matched, indicates a divergence degree between routes of the two swings and a divergence degree between swing speeds of the two swings.

FIGS. 5A and 5B are a diagram for explaining an example of a divergence degree between two swings. An arrow A5 in FIG. 5A indicates a track L1 of the reference swing and a track L2 of the comparative swing, timings of impacts of which are matched and swing speeds of which are substantially the same. When the swing speeds of the reference swing and the comparative swing are substantially the same, the distance from a sample point “t_(n)” to a sample point “t_(n−1)” of the track L1 and the distance from a sample point “t_(n+3)” to a sample point “t_(n+2)” of the track L2 are substantially the same. The distance from a sample point “t_(n−1)” to a sample point “t_(n−2)” of the track L1 and the distance from a sample point “t_(n+2)” to a sample point “t_(n+1)” of the track L1 are substantially the same.

Even if the swing speeds of the two swings are substantially the same, if routes of the two swings are greatly different, the distance between coordinates is large. For example, a route at the sample point “t_(n−2)” of the track L1 and a route at the sample point “t_(n+1)” of the track L2 are greatly different and the distance between a coordinate at the sample point “t_(n−2)” of the track L1 and a coordinate at the sample point “t_(n+1)” of the track L2 is large. That is, even if the two swing speeds are substantially the same, if the routes of the two swings are greatly different, a divergence degree calculated by the divergence-degree calculator 33 is large.

An arrow A6 in FIG. 5B indicates the track L1 of the reference swing and the track L2 of the comparative swing, timings of impacts of which are matched. When swing speeds of the reference swing and the comparative swing are greatly different, the distance from the sample point “t_(n−1)” to the sample point “t_(n−1)” of the track L1 and the distance from the sample point “t_(n+3)” to the sample point “t_(n+2)” of the track L2 are greatly different. The distance from the sample point “t_(n−1)” to the sample point “t_(n−2)” of the track L1 and the distance from the sample point “t_(n+2)” to the sample point “t_(n+1)” of the track L2 are greatly different.

Even if swing routes of the two swings are substantially the same, if swing speeds of the two swings are greatly different, the distance between coordinates is large. For example, the distance between a coordinate at the sample point “t_(n−1)” of the track L1 and a coordinate at the sample point “t_(n+2)” of the track L2 is large. The distance between a coordinate at the sample point “t_(n−2)” of the track L1 and a coordinate at the sample point “t_(n+1)” of the track L2 is large. That is, even if the two swing routes are substantially the same, if the two swing speeds are greatly different, a divergence degree calculated by the divergence-degree calculator 33 is large.

Referring back to FIG. 2, the approximation determiner 34 determines, on the basis of the divergence degree calculated by the divergence-degree calculator 33, whether the reference swing and the comparative swing are approximate to each other. For example, when the distance between a coordinate of the track of the reference swing and a coordinate of the track of the comparative swing is equal to or larger than a predetermined threshold, the approximation determiner 34 determines that the reference swing and the comparative swing are not approximate to each other. Note that, as explained with reference to FIGS. 5A and 5B, the two swings are not approximate to each other because the swing speeds are different, because the swing routes are different, or because the swing speeds and the swing routes are different.

The image generator 35 generates image data of the swing motion analyzed by the motion analyzer 31. The image data includes, for example, a track of a golf club swung by the user and a determination result of the determination by the approximation determiner 34.

The operation of the swing analyzing device 2 is explained below.

FIG. 6 is a flowchart for explaining an operation example of the swing analyzing device 2. When a golf club attached with the sensor unit 1 is swung by the user, the swing analyzing device 2 executes processing of the flowchart shown in FIG. 6. Note that the motion analyzer 31 receives a swing ideal for the user (a reference swing) in advance from the user and calculates coordinates and events of a track of the reference swing.

First, the communicator 23 receives measurement data transmitted from the sensor unit 1 (step S1).

Subsequently, the motion analyzer 31 calculates coordinates of a track of a comparative swing on the basis of the measurement data received in step S1 (step S2).

Subsequently, the event detector 32 detects events of the comparative swing on the basis of the measurement data received in step S1 (step S3). That is, the event detector 32 detects timings of an address, a top, an impact, a downswing, and the like of the comparative swing.

Subsequently, the motion analyzer 31 matches an impact point in time of the coordinates of the track of the reference swing calculated in advance and an impact point in time of the coordinates of the track of the comparative swing calculated in step S2 (step S4).

Subsequently, in step S4, the divergence-degree calculator 33 calculates a space distance between the coordinate of the track of the reference swing and the coordinate of the track of the comparative swing, the impact points in time of which are matched (step S5). When shifting the processing from step S4 to step S5, the divergence-degree calculator 33 calculates a space distance between the coordinates of the two tracks at sample points at an impact time.

Subsequently, the approximation determiner 34 determines whether the space distance calculated in step S5 is equal to or larger than a threshold (step S6). That is, the approximation determiner 34 determines whether the distance between the coordinates of the tracks of the two swings, the impact points in time of which are matched, is equal to or larger than the threshold. If determining that the space distance calculated in step S5 is equal to or larger than the threshold (“Yes” in S6), the approximation determiner 34 shifts the processing to step S7. If determining that the space distance calculated in step S5 is not equal to or larger than the threshold (“No” in S6), the approximation determiner 34 shifts the processing to step S8.

If determining in step S6 that the space distance is equal to or larger than the threshold (“Yes” in S6), the approximation determiner 34 determines that the reference swing and the comparative swing are not approximate to each other (step S7). The approximation determiner 34 outputs a determination result to the image generator 35 and ends the execution of the processing of the flowchart.

If it is determined in step S6 that the space distance is not equal to or larger than the threshold (“No” in S6), the divergence-degree calculator 33 shifts sample points of the tracks of the reference swing and the comparative swing by one point toward the timing of the top and acquires coordinates of the sample points shifted by one point (step S8).

Subsequently, the divergence-degree calculator 33 determines whether the coordinate of the track of the comparative swing acquired in step S8 exceeds a coordinate of the top (step S9). If determining that the coordinate of the track of the comparative swing acquired in step S8 exceeds the coordinate of the top (“Yes” in S9), the divergence-degree calculator 33 shifts the processing to step S10. If determining that the coordinate of the track of the comparative swing acquired in step S8 does not exceed the coordinate of the top (“No” in S9), the divergence-degree calculator 33 shifts the processing to step S5.

If it is determined in step S9 that the coordinate of the track of the comparative swing acquired in step S8 exceeds the coordinate of the top (“Yes” in S9), the approximation determiner 34 determines that the reference swing and the comparative swing are approximate to each other (step S10). The approximation determiner 34 outputs a determination result to the image generator 35 and ends the execution of the processing of the flowchart.

In this way, the divergence-degree calculator 33 of the swing analyzing device 2 matches the impact point in time of the coordinates of the track of the reference swing and the impact point in time of the coordinates of the track of the comparative swing and calculates a divergence degree between the track of the reference swing and the track of the comparative swing. The approximation determiner 34 determines, on the basis of the divergence degree calculated by the divergence-degree calculator 33, whether the reference swing and the comparative swing are approximate to each other. Consequently, the user can objectively grasp whether a swing of the user is good.

The divergence-degree calculator 33 matches the coordinate of the track of the reference swing and the coordinate of the track of the comparative swing at the impact points in time and calculates a divergence degree between the track of the reference swing and the track of the comparative swing. Consequently, the user can objectively grasp whether the swing is good in the downswing from the top to the impact, which is an important indicator of a swing motion.

Note that, in the above explanation, the divergence-degree calculator 33 calculates the divergence degree between the track of the reference swing and the track of the comparative swing. However, the divergence-degree calculator 33 may calculate a divergence degree between an angle of a ball hitting surface of the golf club in the reference swing (equivalent to the second time series information according to the invention) and an angle of a ball hitting surface of the golf club in the comparative swing (equivalent to the second time series information according to the invention) (a difference between the angles of the two ball hitting surfaces). The approximation determiner 34 may determine approximation of the two swings from the angle difference of the ball hitting surfaces of the golf club of the two swings. Note that the angles of the ball hitting surfaces of the golf club are calculated by the motion analyzer 31. For example, the coordinates of the reference swing at the sample points indicated by the arrow A1 in FIG. 3A form the angle of the ball hitting surface of the golf club of the reference swing. The coordinates of the comparative swing at the sample points indicated by the arrow A2 in FIG. 3A form the angle of the ball hitting surface of the golf club of the comparative swing.

In the above explanation, the reference swing and the comparative swing, the divergence degree of which is calculated, is the downswing. However, the reference swing and the comparative swing are not limited to this. For example, the divergence-degree calculator 33 may determine a divergence degree from a halfway down to the impact. That is, the divergence-degree calculator 33 may calculate a divergence degree between the tracks of the reference swing and the comparative swing in a part of the downswing. The reference swing and the comparative swing, the divergence degree of which is calculated, may be a backswing.

The divergence-degree calculator 33 may set the top or the address as the predetermined points in time when the tracks of the reference swing and the comparative swing are matched.

The divergence-degree calculator 33 may change (select), according to operation by the user, the predetermined section where the divergence degree between the reference swing and the comparative swing is calculated. For example, according to operation by the user, the divergence-degree calculator 33 may calculate the divergence degree between the tracks of the reference swing and the comparative swing in the downswing or calculate the divergence degree between the tracks of the reference swing and the comparative swing in the backswing. At this point, the approximation determiner 34 may change the threshold for determining approximation of the two swings in the predetermined section selected by the user. For example, the approximation determiner 34 may set the threshold in the downswing, which is important as a swing motion, smaller than the threshold in the backswing.

When a swing ideal for the user is a swing of another person such as a professional golfer, the tracks of the comparative swing and the reference swing are sometimes different depending on the height of the user and the length of a golf club used by the user. When the swing ideal for the user is a swing in the past of the user, the tracks of the comparative swing and the reference swing are also sometimes different because of a difference in the length of the golf club in use. In this case, the divergence-degree calculator 33 may scale one of the track of the reference swing and the track of the comparative swing and calculate the divergence degree. For example, the divergence-degree calculator 33 receives, from the user, the height of the user and the length of a gold club used for a swing. The divergence-degree calculator 33 acquires information concerning the height of another person who performed an ideal swing and the length of a golf club used when the swing was performed. The divergence-degree calculator 33 may scale one of the track of the comparative swing and the track of the reference swing according to the received height and the received length of the golf club and calculate the divergence degree.

The divergence-degree calculator 33 may calculate a divergence degree (a similarity degree) between a waveform (a shape) of the track of the reference swing and a waveform of the track of the comparative swing. When the divergence degree between the waveform of the track of the reference swing and the waveform of the track of the comparative swing is calculated in this way, only a difference between routes of the two swings appears as the divergence degree. A difference between swing speeds does not appear as the divergence degree. For example, when the divergence degree between the waveform of the track of the reference swing and the waveform of the track of the comparative swing is calculated, as indicated by the arrow A6 in FIG. 5B, if the routes of the two swings are substantially the same, even if the swing speeds of the two swings are greatly different, the divergence degree is small. That is, in this case, it is determined that the two swings are approximate to each other.

When the approximation determiner 34 determines that the reference swing and the comparative swing are not approximate to each other, the sound output section 26 may output sound for notifying the user to that effect. Consequently, the user can recognize, for example, with the sound, whether the swing of the user is approximate to the ideal swing. The user does not have to check a screen of the swing analyzing device 2 every time the user performs a swing.

The invention can also be applied to a swing analyzing device of a camera type. For example, the swing analyzing device of the camera type calculates, with an image analysis, a track of a swing of a golf club photographed by a camera. The divergence-degree calculator 33 calculates a divergence degree between the coordinate of the track of the reference swing and the coordinate of the track of the comparative swing. The approximation determiner 34 determines from the divergence degree calculated by the divergence-degree calculator 33 whether the two swings are approximate to each other.

Second Embodiment

In a second embodiment, a portion of a comparative swing approximate to a reference swing and a portion of the comparative swing not approximate to the reference swing are displayed in different display forms.

FIG. 7 is a diagram showing an example of functional blocks of the sensor unit 1 and the swing analyzing device 2 according to the second embodiment. In FIG. 7, sections same as the sections shown in FIG. 2 are denoted by the same reference numerals and explanation of the sections is omitted.

As shown in FIG. 7, the controller 21 of the swing analyzing device 2 includes an approximation determiner 41 and an image generator 42. When a divergence degree between a track of the reference swing and a track of the comparative swing is equal to or larger than a threshold, the approximation determiner 41 stores, in the storage 22, coordinates of the track of the comparative swing, the divergence degree of which is equal to or larger than the threshold.

The image generator 42 matches predetermine points in time of the tracks of the reference swing and the comparative swing and generates image data including the tracks of the reference swing and the comparative swing in a predetermined section. For example, the image generator 42 matches impacts of the tracks of the reference swing and the comparative swing and generates image data including the tracks of the reference swing and the comparative swing in a downswing.

When generating the image data including the tracks of the reference swing and the comparative swing in the downswing, the image generator 42 generates the image data such that display forms are different in a portion of the comparative swing approximate to the reference swing and a portion of the comparative swing not approximate to the reference swing. For example, the image generator 42 generates the display data such that a display form of the track of the coordinates of the comparative swing (the track determined as not approximate to the reference swing by the approximation determiner 41) stored in the storage 22 is different from a display form of a track of coordinates of the comparative swing not stored in the storage 22.

FIG. 8 is a diagram showing a screen example of the reference swing and the comparative swing. The image data generated by the image generator 42 is output to the display section 25 and displayed on a screen. An image 51 shown in FIG. 8 indicates a screen example displayed on the screen of the display section 25.

A track L11 shown in FIG. 8 indicates a track of the reference swing. A track L12 indicates a track of the comparative swing. A portion of the track L12 of the comparative swing where a divergence degree from the track L11 of the reference swing is equal to or larger than a threshold is displayed in a display form different from a display form of the other portions as shown in the image 51. For example, the portion of the track L12 of the comparative swing where the divergence degree from the track L11 of the reference swing is equal to or larger than the threshold is displayed thicker than the other portions. Note that the thickness of the track is changed in the example of the image 51. However, a color of the track may be changed.

FIG. 9 is a flowchart for explaining an operation example of the swing analyzing device 2. In FIG. 9, kinds of processing same as the kinds of processing in FIG. 6 are denoted by the same reference signs and explanation of the kinds of processing is omitted. In the flowchart of FIG. 9, processing in step S21 and processing in step S22 are different from the flowchart of FIG. 6.

If determining in step S6 that the space distance is equal to or larger than the threshold (“Yes” in S6), the approximation determiner 34 stores, in the storage 22, the coordinates of the track of the comparative swing, the space distance of which is equal to or larger than the threshold (step S21).

If it is determined in step S9 that the coordinate of the track of the comparative swing acquired in step S8 exceeds the coordinate of the top (“Yes” in S9), the image generator 42 generates image data including the track of the reference swing in the downswing and the track of the comparative swing (step S22). In generating the image data, the image generator 42 generates the image data such that a display form of the track of the coordinates of the comparative swing stored in the storage 22 is different from a display form of the track of the other portions. The image generator 42 outputs the generated image data to the display section 25.

In this way, the image generator 42 generates the image data such that the display forms are different in the portion of the comparative swing approximate to the reference swing and the portion of the comparative swing not approximate to the reference swing. Consequently, the user can grasp in which portion a swing of the user is approximate to an ideal swing.

In the above explanation, the image generator 42 changes the display form of the track of the comparative swing. However, the image generator 42 may change the display form of the track of the reference swing. For example, the image generator 42 may generate the image data such that a portion of the track of the reference swing, a divergence degree of which from the track of the comparative swing is equal to or larger than a predetermined threshold, is thicker than the other portions. The image generator 42 may change the display forms of the tracks of both of the reference swing and the comparative swing.

The invention is explained above with reference to the embodiments. However, the functional components of the swing analyzing system are classified according to main processing contents in order to facilitate understanding of the configuration of the system analyzing system. The invention is not limited by a method of classification and names of the components. The components of the swing analyzing system can also be classified into a larger number of components according to processing contents. One component can also be classified to execute a larger number of kinds of processing. The processing of the components may be executed by one kind of hardware or may be executed by a plurality of kinds of hardware.

The processing units of the flowcharts referred to above are divided according to main processing contents in order to facilitate understanding of the processing of the swing analyzing system. The invention is not limited by a method of the division and names of the processing units. The processing of the swing analyzing system can also be divided into a larger number of processing units according to processing contents. One processing unit can also be divided to include a larger number of kinds of processing. The order of processing is not limited to the flowchart.

The technical scope of the invention is not limited to the scope described in the embodiments. It is evident for those skilled in the art that it is possible to add various changes or improvements to the embodiments. For example, the invention can be applied to swing analyzing systems (swing analyzing devices) for various sports such as tennis and baseball. It is evident from the description of the appended claims that forms added with such changes or improvements can also be included in the technical scope of the invention. The embodiments can be combined. The invention can also be provided as a swing analyzing method, a computer program of the swing analyzing device, and a storage medium having the computer program stored therein.

The entire disclosure of Japanese Patent Application No. 2015-094685, filed May 7, 2015 is expressly incorporated by reference herein. 

What is claimed is:
 1. A swing analyzing device comprising: a calculator configured to match a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and a determiner configured to determine, on the basis of the divergence degree, whether the first swing and the second swing are approximate to each other.
 2. The swing analyzing device according to claim 1, wherein the determiner determines, on the basis of whether the divergence degree is equal to or larger than a threshold set in advance, whether the first swing and the second swing are approximate to each other.
 3. The swing analyzing device according to claim 1, wherein the predetermined point in time is an impact.
 4. The swing analyzing device according to claim 1, wherein the divergence degree is a divergence degree calculated in a predetermined section.
 5. The swing analyzing device according to claim 4, wherein the predetermined section is at least a part of a downswing.
 6. The swing analyzing device according to claim 4, wherein the predetermined section is selectable.
 7. The swing analyzing device according to claim 4, wherein the determiner selects a plurality of the predetermined sections, and a value of the threshold for one of the plurality of the predetermined sections is different from a value of the threshold for the other of the plurality of the predetermined sections.
 8. The swing analyzing device according to claim 1, wherein the first time series information is a coordinate of a track of the first swing, the second time series information is a coordinate of a track of the second swing, and the divergence degree is a distance between the coordinate of the track of the first swing and the coordinate of the track of the second swing.
 9. The swing analyzing device according to claim 1, wherein the first time series information is an angle of a ball hitting surface of an exercise instrument in the first swing, the second time series information is an angle of a ball hitting surface of the exercise instrument in the second swing, and the divergence degree is a difference between the angle of the ball hitting surface of the exercise instrument in the first swing and the angle of the ball hitting surface of the exercise instrument in the first swing.
 10. The swing analyzing device according to claim 1, further comprising an image generator configured to generate image data such that display forms are different in a portion where the first swing and the second swing are approximate to each other and a portion where the first swing and the second swing are not approximate to each other.
 11. A swing analyzing method comprising: matching a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and determining, on the basis of the divergence degree, whether the first swing and the second swing are approximate to each other.
 12. The swing analyzing method according to claim 11, wherein the determining includes determining, on the basis of whether the divergence degree is equal to or larger than a threshold set in advance, whether the first swing and the second swing are approximate to each other.
 13. The swing analyzing method according to claim 11, wherein the predetermined point in time is an impact.
 14. The swing analyzing method according to claim 11, wherein the divergence degree is a divergence degree calculated in a predetermined section.
 15. The swing analyzing method according to claim 14, wherein the predetermined section is at least a part of a downswing.
 16. The swing analyzing method according to claim 14, wherein the predetermined section is selectable.
 17. The swing analyzing method according to claim 14, wherein the determining includes selecting a plurality of the predetermined sections, and a value of the threshold for one of the plurality of the predetermined sections is different from a value of the threshold for the other of the plurality of the predetermined sections.
 18. A storage medium having stored therein a computer program for causing a computer to execute: matching a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information; and determining, on the basis of the divergence degree, whether the first swing and the second swing are approximate to each other.
 19. A swing analyzing system comprising: the swing analyzing device according to claim 1; and an inertial sensor.
 20. A swing analyzing device that matches a predetermined point in time of first time series information concerning a first swing and the predetermined point in time of second time series information concerning a second swing to thereby calculate a divergence degree between the first time series information and the second time series information and determines, on the basis of the divergence degree, whether the first swing and the second swing are approximate to each other.
 21. The swing analyzing device according to claim 20, wherein the swing analyzing device determines, on the basis of whether the divergence degree is equal to or larger than a threshold set in advance, whether the first swing and the second swing are approximate to each other.
 22. The swing analyzing device according to claim 20, wherein the predetermined point in time is an impact.
 23. The swing analyzing device according to claim 20, wherein the divergence degree is a divergence degree calculated in a predetermined section. 